Power efficiency of human brains vs. neural networks
126 million artificial neurons at 12.6 Watts, with IBM's True North

Back in 2014, IBM's True North chip was pushing 1 million neurons at less than 100mW.

So that's roughly 126 million artificial neurons at 12.6 Watts.

A mouse has 70 million neurons.

IBM believes they can build a human-brain scale True North mainframe at a "mere" 4kW.

Once 3D transistors come to market, I think we'll catch up to animal brain efficiency pretty fast.